RS-485美制电线标准与国内电缆平方对照表
在以太网和XDSL接入网设计中用到的RS-485接口的通讯电缆,经常会碰到诸如24AWG、26AWG等等表示电缆直径的方法。其实AWG(American Wire Gauge)是美制电线标准的简称,AWG值是导线厚度(以英寸计)的函数。下表是AWG与公制、英制单位的对照表。其中,4/0表示0000,3/0表示000,2/0表示00,1/0表示0。例如,常用的电话线直径为24 AWG 的线径约为0.5mm(0.2mm2),26AWG,约为0.4mm(0.13mm2),AWG数值越大线径越小,平方越小
美制AWG
|
外径
|
截面积(mm2)
|
电阻值(W/km)
|
|
公制mm
|
英制inch
|
|||
4/0
|
11.68
|
0.46
|
107.22
|
0.17
|
3/0
|
10.40
|
0.4096
|
85.01
|
0.21
|
2/0
|
9.27
|
0.3648
|
67.43
|
0.26
|
1/0
|
8.25
|
0.3249
|
53.49
|
0.33
|
1
|
7.35
|
0.2893
|
42.41
|
0.42
|
2
|
6.54
|
0.2576
|
33.62
|
0.53
|
3
|
5.83
|
0.2294
|
26.67
|
0.66
|
4
|
5.19
|
0.2043
|
21.15
|
0.84
|
5
|
4.62
|
0.1819
|
16.77
|
1.06
|
6
|
4.11
|
0.1620
|
13.30
|
1.33
|
7
|
3.67
|
0.1443
|
10.55
|
1.68
|
8
|
3.26
|
0.1285
|
8.37
|
2.11
|
9
|
2.91
|
0.1144
|
6.63
|
2.67
|
10
|
2.59
|
0.1019
|
5.26
|
3.36
|
11
|
2.30
|
0.0907
|
4.17
|
4.24
|
12
|
2.05
|
0.0808
|
3.332
|
5.31
|
13
|
1.82
|
0.0720
|
2.627
|
6.69
|
14
|
1.63
|
0.0641
|
2.075
|
8.45
|
15
|
1.45
|
0.0571
|
1.646
|
10.6
|
16
|
1.29
|
0.0508
|
1.318
|
13.5
|
17
|
1.15
|
0.0453
|
1.026
|
16.3
|
18
|
1.02
|
0.0403
|
0.8107
|
21.4
|
19
|
0.912
|
0.0359
|
0.5667
|
26.9
|
20
|
0.813
|
0.0320
|
0.5189
|
33.9
|
21
|
0.724
|
0.0285
|
0.4116
|
42.7
|
美制AWG
|
外径
|
截面积(mm2)
|
电阻值(W/km)
|
|
公制mm
|
英制inch
|
|||
22
|
0.643
|
0.0253
|
0.3247
|
54.3
|
23
|
0.574
|
0.0226
|
0.2588
|
48.5
|
24
|
0.511
|
0.0201
|
0.2047
|
89.4
|
25
|
0.44
|
0.0179
|
0.1624
|
79.6
|
26
|
0.404
|
0.0159
|
0.1281
|
143
|
27
|
0.361
|
0.0142
|
0.1021
|
128
|
28
|
0.32
|
0.0126
|
0.0804
|
227
|
29
|
0.287
|
0.0113
|
0.0647
|
289
|
30
|
0.254
|
0.0100
|
0.0507
|
361
|
31
|
0.226
|
0.0089
|
0.0401
|
321
|
32
|
0.203
|
0.0080
|
0.0316
|
583
|
33
|
0.18
|
0.0071
|
0.0255
|
944
|
34
|
0.16
|
0.0063
|
0.0201
|
956
|
35
|
0.142
|
0.0056
|
0.0169
|
1,200
|
36
|
0.127
|
0.0050
|
0.0127
|
1,530
|
37
|
0.114
|
0.0045
|
0.0098
|
1,377
|
38
|
0.102
|
0.0040
|
0.0081
|
2,400
|
39
|
0.089
|
0.0035
|
0.0062
|
2,100
|
40
|
0.079
|
0.0031
|
0.0049
|
4,080
|
41
|
0.071
|
0.0028
|
0.0040
|
3,685
|
42
|
0.064
|
0.0025
|
0.0032
|
6,300
|
43
|
0.056
|
0.0022
|
0.0025
|
5,544
|
44
|
0.051
|
0.0020
|
0.0020
|
10,200
|
45
|
0.046
|
0.0018
|
0.0016
|
9,180
|
46
|
0.041
|
0.0016
|
0.0013
|
16,300
|